How do we use classes as types?

It is possible to use a class as an attribute of another class:

bray=# create table junk (id serial PRIMARY KEY, dt DATE NOT NULL);
NOTICE: CREATE TABLE will create implicit sequence 'junk_id_seq' for SERIAL
column 'junk.id'
NOTICE: CREATE TABLE/PRIMARY KEY will create implicit index 'junk_pkey' for
table 'junk'
CREATE

bray=# create table junk1 (j junk, descrip text);
CREATE

But I cannot find any documentation on how to insert a row into junk1.
Nothing I have tried works:

bray=# insert into junk1 values (null, current_date, 'this is text');
ERROR: Attribute 'j' is of type 'junk' but expression is of type 'unknown'
You will need to rewrite or cast the expression
bray=# insert into junk1 values ((null, current_date), 'this is text');
ERROR: parser: parse error at or near ","
bray=# insert into junk1 values ((null, current_date)::junk, 'this is text');
ERROR: parser: parse error at or near "::"
bray=# insert into junk1 (j.dt, descrip) values ( current_date, 'this is
text');
ERROR: parser: parse error at or near "."

etc...

Does anyone know how to get rows into such a table?

--
Oliver Elphick Oliver(dot)Elphick(at)lfix(dot)co(dot)uk
Isle of Wight http://www.lfix.co.uk/oliver
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